Elevator system having door operators



Dec. 17, 1957 H. v. M CORMICK 2,816,625

ELEVATOR SYSTEM HAVING DOOR OPERATORS Filed. Sept. 21, 1956 I5 Sheets-Sheet 1 Dec. 17, 1957 v MCCORMICK 2,816,625

ELEVATOR SYSTEM HAVING DOOR OPERATORS Filed Sept. 21, 1956 5 Sheets-Sheet 2 7 E E A 37;} Q 33 in l 55 27 7 H i: 51B {urea Fig.4.

WITNESSES INVENTOR Harold V. Mc Cormick gm swfdw ATTORNEY United States Patent ELEVATOR SYSTEM IMVING DOOR OPERATURS Harold V. McCormick, Westtield, N. 1., assignor to Westinghouse Electric Corporation, East Pittsburgh, Pa., a corporation of Pennsylvania Application September 21, 1956, Serial No. 611,184

15 Claims. (Cl. 187-52) This invention relates to the operation of multiple doors and has particular relation to the operation of doors in an elevator system having elevator car doors and hoistway doors.

When conveyances are arranged to stop at a plurality of spaced positions of landings, it is customary practice to provide the conveyance and each of the landings with doors for controlling the passage of load between the conveyance and each of the landings. Thus in an elevator system an elevator car is provided with a car door unit and the hoistway for the elevator car may be provided with a separate hoistway door unit for each of the landings served by the elevator car. Each of the door units may include a single door or may include multiple doors. For example, in elevator practice a door unit may include a single door or it may include single-speed center-opening doors or it may include two-spaced center opening or sideopening doors.

In accordance with the invention, multiple doors associated with a conveyance system are divided among plural door operators which are mounted on the conveyance. Thus in an elevator system of a preferred construction one of the door operators mounted on the elevator car may be employed for operating the elevator car door unit. A second door operator mounted on the elevator car may be employed for operating the door unit of any landing at which the elevator car is stopped.

The division of door units between plural door operators results in a material reduction in kinetic energy present during a closing operation of each door unit. For this reason a person struck by a closing door unit would be subjected to substantially less shock than he would receive from a system wherein all door units were operated by a single door operator.

The invention is particularly suitable for elevator systems of the automatic type in which no car attendant is present for the purpose of supervising operation of the door units. In such a system a car door may be provided with a detector responsive to the presence of a person or object in the closing path of the door. Operation of the detector reduces the closing force applied to the door and may initiate a reopening operation of the door. The reduction in kinetic energy permitted by the present invention prompts a rapid stopping of the door.

In some cases it is desirable to prevent excessive movement of one door unit with respect to another door unit. For example, if an elevator car door is stalled it may be desirable to limit independent movement of an associated hoistway door relative to the car door. To this end limit mechanism preferably of shock-absorbing construction may be associated with the doors for limiting movement of one door relative to another associated door.

It is therefore an object of the invention to provide an improved system employing multiple doors wherein the doors are divided between a plurality of door operators each of which controls movement of part only of the doors.

It is another object of the invention to provide a conveyance having a door which serves a plurality of landings each provided with a door with separate door operators mounted on the conveyance for operating the conveyance door and the landing doors.

t is also an object of the invention to provide an elevator system having an elevator car provided with a car door, a hoistway provided with a hoistway door for each landing served by the elevator car and a pair of door operators mounted on the elevator car wherein one of the door operators is arranged to operate the car door whereas the remaining door operator is arranged to operate the door of any landing at which the elevator car is positioned.

It is an additional object of the invention to provide a system as defined in any of the preceding objects wherein a detector is provided which is responsive to presence of an object in the closing path of a door for reducing the closing force applied to such door.

It is a further object of the invention to provide a system as defined in any of the preceding objects wherein limiting mechanism is provided for limiting movement of a door associated with one of the door operators relative to a door associated with another of the door operators.

Other objects of the invention will be apparent from the following description taken in conjunction with the accompanying drawings, in which:

Figure 1 is a view in section through the hoistway of an elevator car showing the top of the elevator car in top plan with parts broken away;

Fig. 2 is a view in front elevation with parts broken away of the elevator car of Fig. 2 located in its hoistway;

Fig. 3 is a view taken on the line IIl-III in Fig. 1;

Fig. 4 is a view in side elevation of the elevator car of Fig. l in association with its hoistway with parts broken away;

Fig. 5 is a detail view in section with parts broken away in a coupling mechanism suitable for coupling a door operator to a door;

Fig. 6 is a schematic view in straight line form showing circuits suitable for controlling the door operators illustrated in Fig. 1;

Fig. 7 is a schematic view showing relays employed in the circuits of Fig. 6. The vertical spacing of relay contacts and coils in Fig. 7 is similar to the vertical spacing of such contacts and coils in Fig. 6; and

Fig. 8 is a view in section with parts broken away showing the elevator car of Fig. 1 in its hoistway.

The association of an elevator car in its hoistway is well known in the art. However, for illustrative purposes Fig. 8 shows an elevator car 1 which is mounted in a hoistway 3 for movement to serve a plurality of landings L, two of which are illustrated in Fig. 8. The elevator car 1 is secured to one end of one or more ropes 5 which pass over a sheave 7 and which are secured at their opposite ends to a counterweight 9. The sheave 7 is controlled in any conventional manner for the purpose of moving the elevator car in its hoistway and stopping the elevator car at any desired landing.

The elevator car 1 is provided with a door unit 11 which is operated to open or close a passage through which load enters and leaves the elevator car. Each of the landings is provided with a hoistway door unit 13 which may be opened or closed for the purpose of permitting passage of load into and out of the elevator car when the elevator car is stopped at a landing. All of the door units are operated by door operating mechanism 15 mounted on the elevator car 1.

Referring now to Figs. 1 to 4, it will be noted that the elevator car 1 is provided with a passage P1 (outlined in dotted lines in Fig. 2) through which load enters and leaves the elevator car. This passage is closed or exposed by operation of the door unit 11. As previously explained, the door unit 11 may be of any conventional construction such as single-spaced center-opening doors or two-speed center-opening or side-opening doors. The specific door unit of Figs. 1 to 4 is of the center-opening single-speed type and comprises two doors 11A and 113. These doors are mounted for reciprocating movement along tracks 17 by means of door hangers 19A and 128 in a conventional manner.

To assure movement of the doors 11A and 11B in unison, these doors are provided with rigid members 21A and 2113 respectively. A flexible device such as a chain or cable 23 has its ends secured respectively to the members 21A and 21B. The flexible device 23 extends around a rotatable pulley 25 which is located to the left of the path of travel of any part associated with the door 11A as viewed in Fig. 2. In an analogous manner a flexible device 27 has its ends connected respectively to the members 21A and 21B and has an intermediate portion extending around a rotatable pulley 29.

By inspection of Fig. 2 it will be noted that when the door 11B is moved to the right a force is transmitted through the flexible devices 27 and 23 to the door 11A for the purpose of moving the door 11A to the left. Consequently the doors are forced to move in unison to open and closed positions.

In order to move the doors 11A and 11B the door operating mechanism 15 includes an electric motor 31 which is coupled to a crank arm 33 through suitable gearing located within a gear case 35. It will be recalled that these components are mounted on the elevator car. The free end of the crank arm 33 is connected pivotally to a link 37 which has its remaining end pivotally connected to one end of a lever 39. The lever 39 is pivotally mounted on a stub shaft 41 which is secured to the elevator car. The lower end of the lever 39 as viewed in Fig. 2 is pivotally connected to one end of a link 43 which has its remaining end pivotally connected to the car door 11B.

By inspection of Fig. 2 it is clear that counterclockwise rotation of the crank arm 33 results in the application of an opening force to the door 11B. Because of the connection between the two doors 11A and 11B the opening force opens both of the doors in unison. Reverse movement of the crank arm 33 results in closure of the doors.

Each of the doors 11A and 11B is provided with a conventional detector for detecting the presence of an object in the closing path of the associated door. The detector for the door 11A may take the form of a safety bar 45A which extends along that edge of the door which is the leading edge during a closing movement of the door. The safety bar 45A is biased relative to the door in the direction of closure of the door. As illustrated in Pig. 2, the mounting of the safety bar may take the form of a plurality of parallel links 47A and 48A each of which has one end pivotally connected to the bar and one end pivotally connected to the door. By in spection of Fig. 2 it will be observed that gravity biases the safety bar 45A toward the right relative to the door 11A. The safety bar 45A controls an electrical switch 45A1. If the bar encounters an object such as the hand of a person located substantially in the closing path of the door 11A, the safety bar is deflected relative to the door to open the normally closed switch 45A1. Such detectors are well known in the art.

The detector for the car door 11B is similar to the detector for the elevator car door 11A and the components thereof are identified by similar reference characters with the exception that the letter A employed for components associated with the door 11A is replaced by the letter B to identify the corresponding components associated with the elevator car door 11B.

Referring to Fig. 3, it will be noted that the hoistway door unit 13 for one of the landings closes and exposes a passage P2 which permits passage of load into and out of the hoistway. It will be understood that when the elevator car is stopped at a landing the passage P1 of the elevator car is aligned with the passage P2 of the landing at which the elevator car is stopped.

In Fig. 3 the door unit 13 is of the center opening type and includes two doors 13A and 13B. These are mounted for reciprocation by means of hangers 51A and 513 which cooperate with tracks 53. The doors 13A and 13B are connected by flexible devices 5'5 and 56 for movement in unison in the same manner by which the doors 11A and 11B are connected.

In order to facilitate opening and closing of the door unit T3, the door unit is provided with a releasable coupling for coupling the door unit to the door operating mechanism 15. This coupling includes a drive block 57 which is secured to the door 13A. The drive block. 57 has a notch 59 (Fig. 5) for releasable reception of an expanding vane mechanism. The expanding vane mechanism includes a fixed vane 61 and a movable vane 63 which is normally biased into the position illustrated in Fig. 5 in full lines. During the initial portion of an opening movement of the door 13A, the movable vane 63 is moved to the position illustrated in broken lines in Fig. 5 for the purpose of providing a firm engagement between the vanes and the drive block 57. The movable vane 63 may be associated with the fixed vane 61 in the manner described in the Rissler et al. Patent 2,502,995 which issued April 4, 1950. In the Rissler et al. patent the vane mechanism is expanded by means of a cam 85. The only difference between the vane mechanism of the Rissler et al. patent and the present showing is that the cam 85 of Rissler is replaced by a roller 65 which is pivotally mounted on an arm 67. During the initial part of a door opening movement the roller 65 engages a cam 69 on the vane 63 for the purpose of forcing the movable vane 63 into its brokenline position.

Referring to Fig. 2, it will be noted that the vane mechanism is mounted on a supporting base 71 to which two parallel links 73 and 75 are pivotally connected. The links 73 and 75 are pivotally associated with stub shafts 77 and 79 which are mounted on the elevator car and which are equidistant respectively from the points of connection of the links 73 and 75 to the base 71. Because of the parallel link mounting, the fixed vane 61 is maintained vertical as viewed in Fig. 2 during movement of the links.

The link 73 has an extension 81 which is pivotally connected to one end of a link 83. This link has its remaining end pivotally connected to the end of the crank arm 85 which is coupled through suitable gearing to an electric motor 87. Conveniently the gearing between the crank arm 85 and the motor 87 may be enclosed in the gear case 35.

When the hoistway door unit 13 is to be opened the motor 87 is energized to rotate the crank arm 85 in a clockwise direction as viewed in Pig. 2. The initial opening movement of the door unit is accompanied by rotation of the arm 67 which is attached to the link 73. This move ment of the arm 67 operates through the roller 65 and the cam 69 to expand the vane mechanism into the drive block 57. Movement of the vane mechanism carries with it the door 13A. Since the door 13A is connected to the door 13B, the door 13B is simultaneously opened.

During an opening movement of the door unit 13. some Vertical motion takes place between the vane mechanism and the drive block 57. These parts may be constructed of steel or some other material which permits such sliding movement.

Suitable connections may be provided for energizing the motors 31 and 87 simultaneously to open and close the associated door units. Satisfactory circuits are illus- 5 trated in Fig. 6 and these circuits now will be discussed. In Fig. 6- a suitable source of direct current is represented by a positive bus L+1 and a negative bus L1. It will be noted that the motor 31 includes an armature 31a and a field winding 31f.

List of apparatus associated with motor 31 OR-door opening relay GR-door closing relay GS-car switch 1K-first opening resistor relay 2Ksecond opening resistor relay 3Kfirst closing resistor relay LO-limit switch on opening (operated by controller) LClimit switch on closing (operated by controller) OL1first opening cam on door (operated by controller) OL2second opening cam on door (operated by controller) CL3--first closing cam (operated by controller) GL4-second closing cam (operated by controller) Adetector relay in the foregoing list it will be noted that certain components are listed as operated by the controller. These components are mechanically operated to open or close a switch when the door reaches a predetermined position. Such components are well known in the art.

When the elevator car door unit is to be opened the armature 31a and the held winding 31 together with the resistor r3 are connected in series across the buses as a result of closure of the make contacts R3 and 0R4. Such closure energizes the field winding 31 with proper polarity for an opening operation of the door unit when the elevator car door unit is to be closed. The armature 31a, the field winding 31 and the resistor r3 are also connected in series by closure of the make contacts CR3 and CR4. This energizes the field winding 31 with proper polarity for a closing operation.

The speed of the motor 31a during a closing or opening operation is controlled by the effective value of the resistor r4, which is connected in shunt across the armature 31a by operation of the make contacts 2K2, 1K2, CR5 and 3K2 together with operation of the second closing cam GL4 operated by the controller.

The first closing resistor relay 3K is connected across the buses through the make contact CR6 of the door closing relay and the switch operated by the first closing cam GL3.

The first opening resistor relay 1K and the second opening resistor relay 2K can be energized only if the make contacts 0R5 are closed to indicate that the door unit is being opened. In addition, for energization of the relay 1K the switch operated by the first opening cam 0L1 must be closed. An additional requirement for energization of the relay 2K is that the switch operated by the second opening cam must be closed.

For present purposes it will be assumed that the manually operated switches 113 and ii?) are open. it will be assumed further that the manually operated switch 115 is open and that the detector relay A is energized. This means that the break contacts All are opened and the make contacts A2 are closed. Under such circumstances operation of the car switch CS to engage the contact CS1 connects the door opening relay DR for energization through the circuit L-l-l, CR7, OR, LO, CS1, CS, Lll. T he limit switch LO opens as the door unit 11 reaches its fully open condition.

if the car switch CS is operated to engage the contact CS2, the following energizing circuit is established for the door closing relay GR: L-|-'i'., A2, 0R7, GR, LG, CS2, CS, L1. The limit switch LC is opened as the door unit 11 reaches its fully closed condition.

The detector relay A is connected in series across the buses L+1 and L-1 through the switches 45A1 and 45B1.

The operation of the motor 31 to open and close the door unit 11 now will be considered.

It will be assumed that the car is in operation and is slowing down to stop at the third floor. The controller switches GL4, GL3 and LO are closed by reason of the position of the controller G0.

As the car comes into the third floor, it is assumed that the attendant throws the car switch CS to open the car doors 11A and 11B. The closing of the contact members CS1 energizes the door opening relay OR by the circuit L-l-l, CR7, OR, LO, CS1, CS, L1.

The closing of the contact members CR3 and 0R4 energizes the field winding 31 and the armature 31a of the motor 31 to move the car doors to their open positions through the circuit L+1, 0R3, 31f, 0R4, r3, 31a, L-l. The energized motor moves the lever 39 to open the car doors and the action of the chains rotates the controller CO to restore its limit switch contact members LC to their closed position. By the time the doors are approximately one inch open, the chains rotate the controller to restore its contact members GL4 to their open position. When the doors are, say, four inches open, the controller restores its contact members GL3 to their open position. As the car doors continue their travel toward their open position and are, say, four inches from their full open position, the controller CO closes its first decelerating contact members 0L1, thereby energizing the first opening resistor realy 1K which, in turn, closes its contact members. The closing of the contact members 1K2 inserts a predetermined portion of the resistor 14 in parallel with the armature 31a of the motor 31 to decelerate that motor to slow down the car doors as they near their full open position. As the doors arrive at, say, one inch from their full open position, the controller CO is operated to close its second decelerating switch 0L2, thereby energizing the second opening resistor relay 2K to close its contact members by the circuit L-i-l't, 2K, 0L2, 0R5, L1. The closing of the contact members 2K2 inserts a predetermined portion of the resistor r4 in parallel with the armature 31a of the motor 31 to decelerate that motor to slow down the car doors so that they move softly into their full open position.

In the diagram of Fig. 6, the resistor 14 is shown as connected at various points by adjustable arrows controlled by opening and closing switches. It should be understood that in actual practice the circuits controlled by the opening and closing switches may be connected to the resistor at any point or points selected by the ele vator engineer and that it is common practice to make these connections when the elevator is installed and to change or modify them in any manner desired to secure smooth operation of the motor 31 in opening and closing the doors with which they are associated.

As the car doors reach their open position, the controller CO is operated to open its limit switch L0 to deenergize the opening relay OR. The opening of the contact members CR3 and CR4 deenergizes the field winding 31 and the armature 31a of the motor 31, thereby stopping that motor. The opening of the contact members 0R5 deenergizes the first opening and the second opening resistor relays 1K and 2K to open their contact members for disconnecting the resistor r4 from the circuits for the armature 31a.

it will be assumed now that the passengers have entered or left the car and that the car attendant moves the car switch CS in a clockwise direction to effect the closing of the car doors. The movement of the switch closes its contact members CS2, thereby energizing the door closing, relay GR through the circuit L+1, A2, 0R7, CR, LC, CS2, Cs, L1.

The closing of the contact members CR3 and CR4 energizes the car door motor C through the circuit L+1, CR4, 31f, CR3, r3, 31a, and L1. The energized motor 31 moves the car doors toward their closed position and 7 in doing so, causes the chains 23 and 27 to rotate the controller CO so that it restores the limit switch L to its closed position. As the car door moves, say, one inch away from its open position, the controller restores its switch OLE to its open position, and as the car doors move, say, four inches away from open position, the controller restores the switch 0L1 to its open position, to prepare them for closing at the proper time in the opening sequence of the doors.

As the doors arrive at, say, four inches from their closed position, the controller CO closes its switch CLS, thereby completing the circuit for energizing the first closing resistor relay 3K to close its contact member 3K2. The closing of the contact members 3K2 inserts a predetermined portion of the resistor rd in parallel with the armature 31a of the motor 31 to cause that motor to decelerate and thus slow down the movement of the car doors as they near their fully closed position.

As the car doors get within, say, one inch of closed position, the controller CO closes its switch GL4, thereby inserting a predetermined portion of the resistor r4 in parallel circuit with the armature 31a to positively check the motor as the car doors reach the desired predetermined distance from full closed position.

When the doors are adjacent their fully closed position, the controller opens its limit switch LC, thereby openins the circuit for the door closing relay CR. When the relay CR becomes deenergized, it opens its contact members. The opening of the contact members CR3 and CR4 deenergizes the motor The opening of the contact members CR5 removes a predetermined portion of the resistor rd from the circuit of the armature 31a of the motor. The opening of the contact member CR6 deenergizes the first closing resistor relay 3K which restores its contact member 3K2 to its open position. Next it will be assumed that as the doors are closing a detector engages an object to open the switch A1.

As shown in Fig. 6, opening of the switch 45All interrupts the energizing circuit for the detector relay A. This relay opens its make contacts A2 to deenergize the door closing relay CR. The relay CR opens its contacts CR3 and to stop the closing movement of the door. Also contacts CR5, CR6 and CR7 are reset.

The detector relay A also closes its break contacts A1 to establish, when the contacts CR7 close, the following opening circuit for the door opening relay: L-l-l, CR7,

R, LO, A1, Ll. Since the door opening relay OR now is energized. it operates in a manner previously described to open the doors. The extent of the reopening of the door may be controlled as desired. Thus, the relay A may have a delay in pickup sufficient to assure full reopening of the door even though the detector operation is brief. For present purposes, it will be assumed that the relay A picks up fairly promptly when energized.

Full door reopening also may be assured by closing the manual switch 115 to connect the make contacts 0R8 across the contacts Ail. When an opening operation of the door is initiated the make contacts 0R8 close to shunt the contacts Al and the door open contacts of the switch CS until the door is fully open.

When the detector is cleared, the relay A picks up to permit a normal door closing operation of the elevator car doors.

The relays OR and also control energization of the motor 527 and the association of these relays with the motor 37 is clearly shown in Fig. 6. In addition, components for checking the speed of t 13 motor 87 are similar to those employed for the motor 31 and are identified by the same reference characters with the exception that a prefix X is applied to each of the corresponding reference characters which is associated with the motor 87. It will be understood that operation of the relays OR and CR results in similar operations of the motors 87 and 31. For this reason the operation of the motor 37 will be understood from the foregoing discussion of the operation of the motor 31.

Inasmuch as the motors 31 and 87 are associated with different doors, it is possible that they will not reach their fully open or fully closed positions at exactly the same time. For this reason the switch 111 should be closed to connect the limit switch XLO which is associated with the door unit 13 in parallel with the corresponding limit switch LO which is associated with the door unit 11. Also the switch 113 is closed to connect the limit switch XLC associated with the door unit 13 in parallel with the corresponding limit switch LC associated with the door unit ill. Consequently, during an opening operation of the doors if the door unit 11 reaches its fully open condition prior to the door unit 13', the opening of the limit switch LO cannot terminate the energization of the door opening relay OR for the reason that tie limit switch XLO is still closed. When the door unit 13 finally reaches its fully open position, the limit switch XLO opens to interrupt the energization of the relay OR. Similar comments apply to the limit switches LC and XLC during a closing operation of the door units.

From the foregoing discussion it will be understood that the door units 11 and 13 are opened and closed by separate door operators. For this reason the kinetic energy developed by each door unit during a closing operation is materially less than the kinetic energy which would be present if all door units were connected to a single door operator. Consequently if one of the door units were to strike an object in the closing path of such door unit, the shock would be substantially less than that present when all door units are operated by a common door operator. In addition, the reduced kinetic energy permits a more rapid stopping of the door units following an operation of one of the detectors.

If the door unit it were to stall during a closing operation without operation of the detectors or if no detectors were provided, the door unit 13 might continue to close for the reason that it has an independent operator associated therewith. In order to limit such independent motion of the door unit 13 relative to the door unit 13, limit mechanism is provided. This may take the form of a block 91 (Fig. 2 secured to the door MA in the path of travel of the vane mechanism. if the door unit 13 moves in the closing direction relative to the door unit ll, the vane mechanism finally strikes the block 91 to prevent further movement of the door unit if: relative to the door unit 11. Preferably shock absorbing mechanism is em ployed for reducing the shock resulting from the impact of the vane mechanism against the block 91. Conveniently the block 91 may be made of a shock absorbing material such as an elastomer. The elastomer may be natural rubber, synthetic rubber or a suitable resin.

If a person were located in the closing path of the elevator car doors, and if the door 11A were to strike such person and come to a stop without initiating a reversing movement of the door unit 13, the door unit would continue its closing movement until the vane m chanism struck the block 31. At this time too door unit 13 would stop. Thus the person would be subjecter. to two light impacts which would not seriously inconvenience him.

Although the invention has been described with reference to certain specific embodiments thereof, numerous modifications falling within the spirit and scope of the invention are possible.

I claim as my invention:

1. In a closure system, a structure having a plurality of landing stations, a conveyance mounted for movement relative to the structure between said stations, said conveyance and any of the stations at which the conveyance is stopped having passages through which load may pass between the conveyance and the station at which the conveyance is stopped, a first door mounted on the conveyance for movement to close and expose the conveyance passage, a separate second door at each of the stations mounted for movement to close and expose the passage of the associated station, first motor operating means mounted on the conveyance operable for moving the first door relative to the conveyance, and second motor operating means mounted on the conveyance operable for moving the second door of any of the stations at which the conveyance is stopped.

2. In a closure system, a structure having a plurality of landing stations, a conveyance mounted for movement relative to the structure between said stations, said conveyance and any of the stations at which conveyance is stopped having passages through which load may pass between the conveyance and the station at which the conveyance is stopped, a first door mounted on the conveyance for movement to close and expose the conveyance passage, a separate second door at each of the stations mounted for movement to close and expose the passage of the associated station, first motor operating means mounted on the conveyance operable for moving the first door relative to the conveyance, second motor operating means mounted on the conveyance operable for moving the second door of any of the stations at which the conveyance is stopped, and limit means for limiting move ment of one of the motor operating means relative to the other of the motor operating means in door-closing direction to a distance substantially less than the closing distance of such motor operating means.

3. In a closure system, a structure having a plurality of landing stations, a conveyance mounted for movement relative to the structure between said stations, said conveyance and any of the stations at which the conveyance is stopped having passages through which load may pass between the conveyance and the station at which the conveyance is stopped, a first door mounted on the conveyance for movement to close and expose the conveyance passage, a separate second door at each of the stations mounted for movement to close and expose the passage of the associated station, first motor operating means mounted on the conveyance operable for moving the first door relative to the conveyance, second motor operating means mounted on the conveyance operable for moving the second door of any of the stations at which the conveyance is stopped, and limit means for limiting movement of one of the motor operating means relative to the other of the motor operating means in door-closing direction to a distance substantially less than the closing distance of such motor operating means, said limit means comprising a shock-absorbing device for gradually stopping said relative movement.

4. In a closure system, a structure having a plurality of landing stations, a conveyance mounted for movement relative to the structure between said stations, said conveyance and any of the stations at which the conveyance is stopped having passages through which load may pass between the conveyance and the station at which the conveyance is stopped, a first door mounted on the conveyance for movement to close and expose the conveyance passage, a separate second door at each of the stations mounted for movement to close and expose the passage of the associated station, first motor operating means mounted on the conveyance operable for moving the first door relative to the conveyance, second motor operating means mounted on the conveyance operable for moving the second door of any of the stations at which the conveyance is stopped, and limit means for limiting movement of one of the motor operating means relative to the other of the motor operating means in door-closing direction to a distance substantially less than the closing distance of such motor operating means, said limit means comprising a lost-motion coupling between said motor operating means, said lost-motion coupling including an elastomer member for gradually stopping said relative movement.

5. in a closure system, a structure having a plurality of landing stations, a conveyance mounted for movement relative to the structure between said stations, said conveyance and any of the stations at which the conveyance is stopped having passages through which load may pass between the conveyance and the station at which the conveyance is stopped, a first door mounted on the conveyance for movement to close and expose the conveyance passage, a separate second door at each of the stations mounted for movement to close and expose the passage of the associated station, first motor operating means mounted on the conveyance operable for moving the first door relative to the conveyance, second motor operating means mounted on the conveyance operable for moving the second door of any of the stations at which the conveyance is stopped, each of the motor operating means including a motor, an operating unit and mechanism coupling the motor to the operating unit, and a common enclosure for the mechanism of both of the motor operating means.

6. in a closure system, a structure having a plurality of: landing stations, a conveyance mounted for movement relative to the structure between said stations, said conveyance and any of the stations at which the conveyance is stopped having passages through which load may pass between the conveyance and the station at which the conveyance is stopped, a first door mounted on the conveyance for movement to close and expose the conveyance passage, a separate second door at each of the stations mounted for movement to close and expose the passage or" the associated station, first motor operating means mounted on the conveyance operable for moving the first door relative to the conveyance, second motor operating means mounted on the conveyance operable for moving the second door of any of the stations at which the conveyance is stopped, detector means responsive to presence of an object substantially in the closing path of at least one of the doors, and means responsive to operation of the detector means for substantially reducing the closing force acting on at least one of toe doors.

7. In a closure system, a structure having a plurality of landing stations, a conveyance mounted for movement relative to the structure between said statitons, said conveyance and any of the stations at which the conveyance is stopped having passages through which load may pass between the conveyance and the station at which the conveyance is stopped, a first door mounted on the conveyance for movement to close and expose the conveyance passage, a separate second door at each of the stations mounted for movement to close and expose the passage of the associated station, first motor operating means mounted on the conveyance operable for moving the first door relative to the conveyance, second motor operating means mounted on the conveyance operable for moving the second door of any of the stations at which the conveyance is stopped, joint energizing means e ective when operated to energize both of the motor operating means to close the first door and the second door of a station at which the conveyance is stopped, said motor operating means acting to produce simultaneous closing movement of the last-named two doors during substantial portions of the closing movement of each of said two doors, detector means responsive to presence of an object substantially in the closing path of at least one of the two lastnamed doors, and means responsive to operation of the detector means as the two last-named doors close for substantially reducing the closing force acting on each of the doors.

8. in a closure system, a structure having a plurality of landing stations, a conveyance mounted for movement relative to the structure between said stations, said conveyance and any of the stations at which the conveyance is stopped, a first door mounted on the conveyance for movement to close and expose the conveyance passage, a separate second door at each of the stations mounted for movement to close and expose the passage of the associated station, first electric motor operating means mounted on the conveyance operable for moving the first door relative to the conveyance, second electric motor operating means mounted on the conveyance operable for moving the second door of any of the stations at which the conveyance is stopped, and checking means responsive to arrival of the doors adjacent a position at which the doors are to stop for connecting the associated motor operating means for electrical checking of the doors.

9. In an elevator system, an elevator car having a passage through which load enters and leaves the elevator car, a first door mounted for movement relative to the elevator car to close and open the passage, first door operating means including a first operating motor mounted on the elevator car for moving the door between open and closed positions, and second door operating means including a second operating motor mounted on the elevator car, said second door operating means having movable door-coupling device accessible, whereby a second door may be coupled to the second door-operating means.

10. In an elevator system, an elevator car having a passage through which load enters and leaves the elevator car, a first door mounted for movement relative to the elevator car to close and open the passage, first door operating means including a first operating motor mounted on the elevator car for moving the door between open and closed positions, second door operating means including a second operating motor mounted on the elevator car, said second door operating means having movable door-coupling device accessible, whereby a second door may be coupled to the second door-operating means, means for energizing said motors for operation substantially simultaneously, and means for limiting movement of the door-coupling means independently of the first door during a door-closing operation.

11. In an elevator system, an elevator car having a passage through which load enters and leaves the elevator car, a first door mounted for movement relative to the elevator car to close and open the passage, first door operating means including a first operating motor mounted on the elevator car for moving the door between open and closed positions, second door operating means including a second operating motor mounted on the elevator car, said second door operating means having movable door-coupling device accessible, whereby a second door may be coupled to the second door-operating means, cetector means responsive to the presence of an object substantially in the closing path of the first door, and means responsive to operation of the detector means for reducing the door closing force available from the motors.

12. In an elevator system, an elevator car having a passage through which load enters and leaves the elevator car, a first substantially planar door mounted for reciprocation in the plane of the door to close and open the passage, first door operating means including a first operating motor mounted on the elevator car for moving the door between open and closed positions, and second door operating means including a second operating motor mounted on the elevator car, said second door operating means having a door coupling device external to the elevator car adjacent said door and means operated by the second operating motor for moving the door coupling device independently of the door in directions having a substantial component parallel to the direction of reciprocation of the door, whereby a second door may be coupled to the door coupling device for movement by the second door operating means.

13. In an elevator system, an elevator car having a passage through which load enters and leaves the elevator car, a first substantially planar door mounted for reciprocation in the plane of the door to close and open the passage, first door operating means including a first operating motor mounted on the elevator car for moving the door between open and closed positions, and second door operating means including a second operating motor mounted on the elevator car, said second door operating means having a door coupling device external to the elevator car adjacent said door, means operated by the second operating motor for moving the door coupling device independently of the door in directions having a substantial component parallel to the direction of reciprocation of the door, whereby a second door may be coupled to the door coupling device for movement by the second door operating means, and a limit device secured to the door in the path of movement of the door coupling device for limiting movement of the door coupling device independently of the door in at least one direction of. travel, one of said devices having a shock absorbing construction for absorbing shock resulting from engagement of said devices.

14. In an elevator system, an elevator car having a passage through which load enters and leaves the elevator car, a substantially planar door assembly for opening and closing the passage, said door assembly comprising first and second center-opening doors mounted for reciprocation between open and closed positions, means coupling the doors for movement towards and away from each other, first door operating means including a first operating motor mounted on the elevator car, said door operating means comprising linkage coupling the operating motor to the first door for applying closing and opening forces to the first door, and second door operating means including a second operating motor mounted on the elevator car, said second door operating means comprising a door coupling device located outside the elevator car adjacent the second door and means coupling the door coupling device to the second operating motor for movement by the motor in a direction having at least a substantial component in the direction of said reciprocation.

15. In an elevator system, an elevator car having a passage through which load enters and leaves the elevator car, a substantially planar door assembly for opening and closing the passage, said door assembly comprising first and second center-opening doors mounted for reciprocation between open and closed positions, means coupling the doors for movement towards and away from each other, first door operating means including a first operating motor mounted on the elevator car, said door operating means comprising linkage coupling the operating motor to the first door for applying closing and opening forces to the first door, second door operating means including a second operating motor mounted on the elevator car, said second door operating means comprising a door coupling device located outside the elevator car adjacent the second door and means coupling the door coupling device to the second operating motor for movement by the motor in a direction having at least a substantial component in the direction of said reciprocation, and a limit device secured to the second door at a position intermediate the door coupling device and the edge of the second door which is the leading edge during a door closing movement, said limit device being positioned in the path of movement of the door coupling device to limit movement of the door coupling device relative to the second door in the door closing direction, one of said devices being of shock absorbing construction for absorbing shock resulting from engagement of the devices.

No references cited. 

